Field of the Invention
The present disclosure generally relates to the field of apparatus for manufacturing liquid crystal displays, and particularly, to a belt transmission device and a grinding apparatus.
Description of the Related Art
Usually, in a process of manufacturing a thin film transistor liquid crystal display (TFT-LCD), a glass substrate is firstly cleaned and ground, and then thin film transistors are produced on the glass substrate.
In the existing grinding apparatus for a glass substrate, a belt transmission device is used for driving to realize grinding. This belt transmission device generally comprises a grinding stand and four rotation wheels provided at four corners of the grinding stand. The four rotation wheels are used for supporting a grinding belt, provide a tension force to the grinding belt. The four rotation wheels include one driver wheel and three driven wheels. The driver wheel is driven by a driving motor to rotate, which in turn drives the three driven wheels to rotate by means of the grinding belt supported by the rotation wheels. In this way, transmission of the grinding belt is realized finally.
In the existing grinding apparatus for the glass substrate, however, since it is needed to provide a sufficient tension force to the grinding belt and thus the positions of the driver wheel and the three driven wheels are fixed, there is a problem that the grinding belt cannot be mounted and detached easily. Moreover, after the grinding belt has been used for a period of time, its tension force will change, causing the grinding belt to slip on the driver wheel or the driven wheels or even fall off the wheels. In the existing grinding apparatus, there is no device provided for adjusting the tension force of the grinding belt, no device provided for detecting the rotation speed of the grinding belt in real-time, and no device provided for detecting and feeding back slipping and falling-off of the grinding belt. Thus, when the rotation speed of the grinding belt changes, and even when the grinding belt slips on the wheels or falls off from the wheels, an operator cannot deal with these problems in time, so that the apparatus may delay or stop, utilization of the apparatus may be adversely influenced, productivity thereof may be reduced, and product yield of the glass substrate may also be adversely influenced.